In a large skillet, heat the olive oil and butter over medium-high heat. Add the sliced onions and cook, stirring occasionally with a wooden spoon, until they start to soften, about 10 minutes. Reduce to low heat, and continue to cook the onions, stirring occasionally, until they are golden brown and caramelized, about 30-45 minutes. Then add the balsamic vinegar and scrape the bottom of the pan to get all the brown bits. Season with a pinch of salt and pepper to taste. Set aside to cool slightly.

Pre heat oven to 400°F (200°C). Line a baking sheet with parchment paper. On a lightly floured surface, roll out the puff pastry sheet to smooth the edges and slightly thin it out. Cut the puff pastry into 1.5 inch squares and place the small squares on the prepared baking sheet.

Brush each square with the beaten egg wash. Bake in the oven for 10-15 min until they're puffed up and golden brown.

While the puff pastry is baking, make the hot honey by mixing in the cayenne pepper with the honey.

Assemble the bites by placing a small spoonful of balsamic caramelized onions on each puff pastry square. Top with a small pieces of crumbled blue cheese. Top with chopped chives and drizzle with the spicy honey.